Yellowing/black spots on squash

Asked August 9, 2016, 5:00 PM EDT

ON our Squash plants, Zucchini, even pumpkin plants...every year they seem to get the same diseases...bloom rot, yellowing leaves, brown curled edges, and some with black spots but mostly all with a whitish mold on the leaves. I have used Blosum end rot (calcium) and sprayed with a fungicide several times. They start to get new green leaves and then if I don't spray every few days, the entire plant immediately gets the same issues. Incidently we have all 3 plants, plus a couple of pepper plants in the same 8'X4' raised bed. We rotate every year, but get the same results. We live in NW Montana on the West side of Flathead lake. Thanks for any help you can offer.

Flathead County Montana

1 Response

If you can bring a sample to your county extension office, your extension agent Pat McGlynn can either identify the issue, or send the sample to the MSU diagnostic lab to get the issue identified. Because you are having issues across genera (squash and peppers) i believe it may be an environmental issue such as a nutrient deficiency or toxicity.

Your local County Extension office locally is

Flathead County
1108 S. Main Street, Suite #4
Kalispell MT, 59901


Lake County
300 Third Ave. NW
Ronan MT, 59864-2328

Finally, if you would send some pictures, I might be able to get a better idea of the issue. From your description, it could be many different problems.